1. Field of the Invention
The present invention generally relates to a light guiding plate and a keystroke module for use therewith, in particular, to a light guiding plate and a keystroke module that are used for electronic devices.
2. Description of Prior Art
Following the progress and development of technology, electronic devices, for example, mobile phone, personal digital assistant, and so on, have become necessary information appliances used by modern people. All these electronic devices have keystroke module, with which information transmission between the user and the electronic device may be provided, or with which various functions of electronic device may be executed. In addition, in order to provide user to operate each key button of keystroke module under dark circumstance, a light guiding plate and a light source are disposed in the keystroke module, whereby the light source emits out light, which is then reflected by the light guiding plate in a way, such that a user can clearly identify each key button's position, figure, and number in the darkness. According to aforementioned arrangements, the key pressing operation may be easily executed, and the using function endowed to the electronic device may be further enhanced significantly.
The keystroke module according to the prior arts mainly includes: a contacting and controlling layer, a light guiding plate, and a light source, wherein the contacting and controlling layer has a pressing side and a contacting and light guiding side; the light guiding plate is arranged under the contacting and light guiding side of the contacting and controlling layer and has a hard plate body, side of which is formed as an incident side, and top side of which is formed as an emitting side, under which a reflecting side is formed correspondingly; the light source is arranged at one side of the light guiding plate for irradiating light from the incident side, then the irradiated light is reflected by the reflecting side of the light guiding plate, and finally, the light is emitted out from the emitting side; thereby, a keystroke module is constituted.
However, in the keystroke module of the prior arts, following drawbacks are still existent under practical application: first of all, since its light guiding plate is a hard plate body, so it is easy for each component contacted with the light guiding plate to generate wearing damage under the pressing operation of longtime and high frequency, besides the touching feeling of keystroke being very poor; second, a spring membrane, having plural metallic springs, is usually arranged under the light guiding plate, and its surface easily generates plastic deformation, after being frequently contacted and pressed by the light guiding plate, the using lifetime of light guiding plate or keystroke module being significantly shortened; third, in order to reach an excellent effect of reflection for the light guiding plate, its thickness is difficult to be minimized, which is further contradictory to the pursuing advantages of the common electronic devices—lightness, thinness, shortness, and smallness—not only the assembly and connection for each component are tedious and inconvenient, but also the material cost of components can not be reduced effectively. All these drawbacks are needed to be solved urgently.